The Merc no longer has a recipe, now you have to hire him in a mercenary post which can be found around the world

Will stand still on the Mercenary post until you hire him.

Give him a gold ingot and he will fight for you.

Right click to tell him to stay and wait.

They will not despawn if hired.

Attack monsters on sight.

Mercenarys have two textures. One when they are told to wait and one when they are following the player.

Following Mercenary:

Mercenary post in the wilds:

The Medallion

The Medallion is an item found inside enemy castles. Right now there only use is to make your defender NPC follow you. (Like animals following wheat)

Enemy Castles

Enemy castles is generated in the world. These castles contains chest where you can find varius items. They are however heavily defended. TNT is a good way of take them out.There are two castle types one with an extra tower.(Nothing special there yet)

In the middle of the castle there is an ememy knight spawner and the walls are filled with enemy archer spawners. The Enemy archerspawner looks like a dark cobblestone block. The knight spawner look like a red stick.

Castle Defenders Recipes

You start with building a block for the mobs to spawn on. Like this:

Bow = Archer Block

Sword = Knight Block

Castle Defenders Changelogs

v2.4

Hold up a medalion to get your Defenders to follow you. (Found in enemy castles)